Diagnostic microbiology and infectious disease最新文献

{"title":"Genetic diversity of plasmodium vivax merozoite surface protein 3α and β field isolates","authors":"Nargis Shaheen ,&nbsp;Asma Ashraf ,&nbsp;Nida Malik ,&nbsp;Muneeba Naeem ,&nbsp;Ismail Zeb ,&nbsp;Ghulam Nabi ,&nbsp;Maher S. Alwethaynani ,&nbsp;Rania Ali El Hadi Mohamed ,&nbsp;Manal F. Elkhadragy ,&nbsp;Nawal Al-Hoshani","doi":"10.1016/j.diagmicrobio.2026.117352","DOIUrl":"10.1016/j.diagmicrobio.2026.117352","url":null,"abstract":"<div><div><em>Plasmodium</em> parasites are the causative agents of a life-threatening malaria disease, causing a substantial economic loss to the health sectors on a global scale, especially in Pakistan, due to the presence of <em>Plasmodium vivax</em> and <em>Plasmodium falciparum.</em> However, <em>P. vivax</em> is highly prevalent and responsible for approximately 75% malaria infection with limited reports on its genetic diversity. The current study analyzed the genetic diversity of the <em>P. vivax</em> merozoite surface protein 3α and 3β (Pvmsp-3α and β) gene in field isolates of Azad Jammu and Kashmir (AJK) from Pakistan. Blood samples (<em>n</em> = 207) were collected from malaria-suspected patients in health care sectors between March and August 2024 for microscopy and DNA extraction. A nested PCR was performed targeting the Pvmsp-3α and Pvmsp-3β genes, followed by restriction fragment length polymorphism (RFLP) using AluI and PstI restriction enzymes. All microscopically examined samples were positive (207). Among them, PCR assay detected <em>P. vivax</em> in 188/207 (90.82%) samples and <em>P. falciparum</em> in 19/207 (9.18%) samples. Of the PCR-confirmed <em>P. vivax</em> samples, 98/188 (52.13%) and 90/188 (47.87%) were Pvmsp-3α and Pvmsp-3β amplified fragments, showing three and two major allelic variants, respectively. In Pvmsp-3α, the allelic distribution was type A (65/98, 66.33%), type B (11/98, 11.22%), and type C (13/98, 13.27%). Similarly, the allelic frequencies of Pvmsp-3β for type A and B were 69/90 (76.67%) and 21/90 (23.33%), respectively. This exploration of the <em>P. vivax</em> genotypic diversity from AJK is a major contribution to the demonstration of its complexity and polymorphism. The outcomes of the present findings are helpful in understanding the molecular epidemiology of <em>P. vivax</em> and exploring mixed genotype infection for control strategies.</div></div>","PeriodicalId":11329,"journal":{"name":"Diagnostic microbiology and infectious disease","volume":"115 3","pages":"Article 117352"},"PeriodicalIF":1.8,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147387752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of the cefazolin inoculum effect in blood culture-isolated methicillin-susceptible Staphylococcus aureus strains: A Japanese multicenter study","authors":"Shinnosuke Fukushima ,&nbsp;Shuma Tsuji ,&nbsp;Kazuyoshi Gotoh ,&nbsp;Koji Iio ,&nbsp;Sakura Ogawa ,&nbsp;Norihito Koyanagi ,&nbsp;Yuji Ito ,&nbsp;Hiroshi Koganemaru ,&nbsp;Atsushi Yoshida ,&nbsp;Hideharu Hagiya","doi":"10.1016/j.diagmicrobio.2026.117345","DOIUrl":"10.1016/j.diagmicrobio.2026.117345","url":null,"abstract":"<div><h3>Background</h3><div>Cefazolin inoculum effect (CInE) is a microbiological phenomenon where the MIC of cefazolin against methicillin-susceptible <em>Staphylococcus aureus</em> (MSSA) strains increases with higher bacterial volumes.</div></div><div><h3>Method</h3><div>We retrospectively investigated the prevalence and characteristics of the CInE among MSSA strains isolated from blood cultures at three Japanese hospitals. The collected isolates were screened for <em>blaZ</em> using PCR, and the cefazolin minimum inhibitory concentration (MIC) for the <em>blaZ</em>-positive MSSA isolates was measured at standard and high inoculum volumes. CInE-positive MSSA strains were defined as those with a cefazolin MIC ≥16 μg/mL at 10⁷ CFU/mL and ≤8 μg/mL at 10⁵ CFU/mL. In these <em>blaZ</em>-positive strains, we performed <em>blaZ</em> typing and tested a modified nitrocefin-based rapid examination to detect the CInE.</div></div><div><h3>Results</h3><div>We collected 329 MSSA strains isolated from blood cultures. Of these, 96 (29.2%) were positive for the <em>bla</em>Z gene, with the following genotypes: type A (15, 15.6%), type B (3, 3.1%), type C (77, 80.2%), type D (0, 0.0%), and non-type (1, 1.0%). Among 96 <em>bla</em>Z-positive MSSA isolates, 11 exhibited the CInE, all of which harbored <em>blaZ</em> type A. The rapid nitrocefin test detected CInE positivity with high sensitivity (100%), specificity (94.1%), and diagnostic accuracy (94.8%).</div></div><div><h3>Conclusion</h3><div>This study highlighted the low prevalence of CInE-presenting MSSA isolates in Japan. When the cefazolin MIC is ≥1 μg/mL or the penicillin G MIC is ≥0.25 μg/mL, the rapid nitrocefin test may be useful for considering the CInE in patients with high bacterial volume MSSA infections.</div></div>","PeriodicalId":11329,"journal":{"name":"Diagnostic microbiology and infectious disease","volume":"115 3","pages":"Article 117345"},"PeriodicalIF":1.8,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147364029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A case of Legionnaires’ disease linked to the household hot water system, confirmed by whole genome sequencing","authors":"Ani-Ioana Cotar ,&nbsp;Mihaela Oprea ,&nbsp;Sorin Dinu ,&nbsp;Laura-Ioana Popa ,&nbsp;Cătălin Herghelegiu ,&nbsp;Manuela-Luminița Minea ,&nbsp;Roxana-Elena Buzilă ,&nbsp;Alexandru Duhaniuc ,&nbsp;Odette Popovici","doi":"10.1016/j.diagmicrobio.2026.117357","DOIUrl":"10.1016/j.diagmicrobio.2026.117357","url":null,"abstract":"<div><div><em>Legionella pneumophila</em> – an opportunistic bacterial pathogen frequently identified in the environmental water samples – can produce human infections after inhalation of contaminated aerosols. We describe a case of Legionnaires’ disease linked to a household drinking water system. Serogroup 1 <em>L. pneumophila</em> isolates were recovered from both human and environmental samples and were analysed by whole genome sequencing (WGS). Phylogenetic relatedness inferred by core genome multi-locus sequence typing (cgMLST) revealed the household drinking water system as the source of isolates causing human infection. This epidemiological investigation performed in Romania and identifying the source of infection by WGS is the first of this kind for our country. The human and environmental isolates were undoubtedly linked through the use of high-discriminatory WGS analysis, which confirmed the relatedness inferred from the classical seven-loci sequence-based typing (SBT) scheme.</div></div>","PeriodicalId":11329,"journal":{"name":"Diagnostic microbiology and infectious disease","volume":"115 3","pages":"Article 117357"},"PeriodicalIF":1.8,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147375867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Does antibiotic therapy affect multiplex PCR results in community-acquired bacterial meningitis?","authors":"Caroline Reckart ,&nbsp;Elizabeth Aguilera ,&nbsp;Audrey Wanger ,&nbsp;Rafael Bravo-Santos ,&nbsp;Rodrigo Hasbun","doi":"10.1016/j.diagmicrobio.2026.117354","DOIUrl":"10.1016/j.diagmicrobio.2026.117354","url":null,"abstract":"","PeriodicalId":11329,"journal":{"name":"Diagnostic microbiology and infectious disease","volume":"115 3","pages":"Article 117354"},"PeriodicalIF":1.8,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147387748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative evaluation of conventional and nanopore approaches in onychomycosis diagnosis","authors":"Janeth Villanueva-Reyes ,&nbsp;Andrés Mauricio González-Ríos ,&nbsp;Maria del Pilar Crespo-Ortiz ,&nbsp;María Inés Álvarez-Valle","doi":"10.1016/j.diagmicrobio.2026.117348","DOIUrl":"10.1016/j.diagmicrobio.2026.117348","url":null,"abstract":"<div><h3>Background</h3><div>Onychomycosis is a frequent and chronic nail infection caused by dermatophytes, yeast, and non-dermatophyte molds (NDM). Detection of the causative agent is relevant to overcoming recurrent infections and improving treatment. Combined microscopy and culture are the diagnostic gold standard; however, more sensitive tests are needed to speed detection. This work aimed to assess fungal nail diagnosis using conventional and molecular techniques. We explored the potential of nanopore sequencing for fungal detection.</div></div><div><h3>Methods</h3><div>A total of 104 nail samples from 51 patients with onychomycosis and 53 individuals with healthy nails were subjected to potassium hydroxide(KOH) microscopy, culture, PCR, and nanopore sequencing. Sensitivity was calculated using a composite reference standard based on microscopy and culture.</div></div><div><h3>Results</h3><div>Distal subungual onychomycosis was the most frequent clinical presentation (43.1%). Infections were primarily caused by dermatophytes 60% (21), followed by yeast 22.9% (8) and NDM 11.4% (4), 5.7% (2) were mixed infections. The prevalent pathogens were <em>T. rubrum</em> (40%), <em>T. mentagrophytes</em> (14.3%), and <em>C. albicans</em> (14.3%). 90.2% (46/51) of patients were positive by KOH, 68.6% (35/51) by culture (58.8%, 30/51 positive in both), and 58.8%(30/51) were sequenced by nanopore. Fungal DNA sequences were identified in 65.7% (23/35) of culture-positive patients. Eight samples from healthy nails were positive for fungal DNA and were considered transient microbiota.</div></div><div><h3>Conclusion</h3><div>Dermatophytes are the predominant causative agent; however, at least 30% of nail infections are caused by yeast and NDM. Conventional diagnosis remains challenging; alternatively, nanopore sequencing represents a complementary diagnostic tool that should be further optimized for clinical application.</div></div>","PeriodicalId":11329,"journal":{"name":"Diagnostic microbiology and infectious disease","volume":"115 3","pages":"Article 117348"},"PeriodicalIF":1.8,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147372345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mycobacterium avium complex presenting as an infected epidermal inclusion cyst of breast: a rare case report","authors":"Niti Sureka,&nbsp;Shikhar Chohan,&nbsp;Sana Ahuja,&nbsp;TeenaTeena,&nbsp;Sufian Zaheer","doi":"10.1016/j.diagmicrobio.2026.117344","DOIUrl":"10.1016/j.diagmicrobio.2026.117344","url":null,"abstract":"<div><div>Introduction: Non-tuberculous mycobacteria (NTM), including Mycobacterium intracellulare, are opportunistic pathogens mostly affecting immunocompromised individuals. Cutaneous involvement is rare and can mimic other diseases. Epidermal inclusion cysts (EICs) are benign and uncommon in the breast. MAC infection within an EIC is extremely rare and complicates diagnosis.</div><div>Case Presentation: A 21-year-old immunocompetent woman presented with a painful, progressively enlarging right breast mass over six months. Examination revealed an erythematous swelling with draining sinus. Imaging suggested an abscess or infected cyst. FNAC showed squamous cells and inflammation. Ziehl-Neelsen stain and Mycobacteria Growth Indicator Tube (MGIT) culture confirmed MAC. She received amikacin, moxifloxacin, clarithromycin, and linezolid for 12 months with full resolution.</div><div>Conclusion: This case illustrates an unusual MAC infection in a breast EIC in an immunocompetent patient and emphasizes the need for microbiological studies in persistent breast lesions for accurate diagnosis and treatment.</div></div>","PeriodicalId":11329,"journal":{"name":"Diagnostic microbiology and infectious disease","volume":"115 3","pages":"Article 117344"},"PeriodicalIF":1.8,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147375942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adult Japanese encephalitis in a non-endemic area: A case highlighting diagnostic limitations of targeted next-generation sequencing","authors":"LIU Hong-bo","doi":"10.1016/j.diagmicrobio.2026.117370","DOIUrl":"10.1016/j.diagmicrobio.2026.117370","url":null,"abstract":"<div><div>Japanese encephalitis (JE) is a mosquito-borne viral disease that is rarely reported in non-endemic regions. We describe an adult patient presenting with acute meningoencephalitis in northern China, a non-endemic area. Targeted next-generation sequencing (tNGS) performed twice on cerebrospinal fluid was negative because JE virus was not included in the detection panel. The diagnosis was confirmed by a strongly positive JE IgM antibody. This case highlights that tNGS has inherent diagnostic limitations depending on pathogen coverage. In non-endemic areas near endemic regions, JE should be considered in the differential diagnosis, and serologic testing remains essential for accurate diagnosis.</div></div><div><h3>One-sentence summary</h3><div>We report an adult case of Japanese encephalitis from a non-endemic region that was initially missed by targeted next-generation sequencing, emphasizing the need for the combined use of molecular and serological testing in suspected central nervous system infections.</div></div>","PeriodicalId":11329,"journal":{"name":"Diagnostic microbiology and infectious disease","volume":"115 3","pages":"Article 117370"},"PeriodicalIF":1.8,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147387750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diagnostic value of paediatric blood culture bottle allied to MALDI-TOF mass spectrometry in the aetiological assessment of microbial keratitis","authors":"Juliana Mika Kato ,&nbsp;Luiza Manhezi Shin de Oliveira ,&nbsp;Tatiana Tanaka ,&nbsp;Luciana Santana ,&nbsp;Evangelina da Motta Pacheco Alves de Araujo ,&nbsp;Joyce Hisae Yamamoto ,&nbsp;Ruth Miyuki Santo","doi":"10.1016/j.diagmicrobio.2026.117353","DOIUrl":"10.1016/j.diagmicrobio.2026.117353","url":null,"abstract":"<div><h3>Purpose</h3><div>Infectious keratitis remains a sight-threatening condition, yet its aetiological diagnosis is often hampered by low culture positivity, largely due to limited corneal scraping material. Identifying alternative, high-yield methods is crucial to optimise treatment protocols. This study evaluates the diagnostic performance of paediatric blood culture bottles (PBCB) compared with the conventional multi-sampled method. MALDI-TOF mass spectrometry (MS) was used as the standardised identification tool for isolates recovered using both approaches.</div></div><div><h3>Methods</h3><div>This prospective study included patients with infectious keratitis at a tertiary referral centre (2019-2023). Corneal scrapings were cultured using PBCB and, in parallel, using a conventional multi-sampled approach (thioglycolate broth, brain heart infusion broth with antibiotics, blood agar, chocolate agar, Sabouraud dextrose agar). Pathogens were identified by MALDI-TOF MS. Diagnostic agreement between methods was assessed using Cohen’s kappa with 95% confidence intervals.</div></div><div><h3>Results</h3><div>Among 150 corneal scrapings, the overall culture positivity was 49.3%. PBCB yielded positive cultures in 41.3% (62/150) of cases, comparable to the multi-sampled approach (43.3%; 65/150). <em>Pseudomonas aeruginosa</em> was the most frequently isolated pathogen in both methods (22.9% vs 20.8%). Diagnostic agreement between the two techniques was substantial (kappa = 0.69; 95% CI: 0.57-0.80). Of note, the conventional method detected fungal pathogens in some cases where PBCB were negative.</div></div><div><h3>Conclusion</h3><div>PBCB represents an effective diagnostic alternative for bacterial keratitis, performing comparably to conventional multi-sampling. Although standard techniques remain necessary for fungal detection, PBCB offers practical advantages, particularly in small-volume samples. Its use may reduce the number of corneal scrapings required, contributing to a safer diagnostic approach.</div></div>","PeriodicalId":11329,"journal":{"name":"Diagnostic microbiology and infectious disease","volume":"115 3","pages":"Article 117353"},"PeriodicalIF":1.8,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147372322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A case report of rhino-orbital-cerebral invasive infection caused by co-infection with Pleurostoma ootheca and Mucorales","authors":"Ya Liu ,&nbsp;Meng-lan Gui ,&nbsp;Ling Shu ,&nbsp;Tingting Yuan ,&nbsp;Jun-yan Qu ,&nbsp;Mei Kang","doi":"10.1016/j.diagmicrobio.2026.117341","DOIUrl":"10.1016/j.diagmicrobio.2026.117341","url":null,"abstract":"<div><div>Pleurostoma species are rare opportunistic fungal pathogens that primarily infects immunocompromised hosts, causing phaeohyphomycosis, manifesting as localised superficial or deep infections, pulmonary infections, central nervous system infections, or disseminated diseases. Fungi of the order Mucorales are known to cause rapidly progressive infections in the lungs, rhino-orbital-cerebral regions, and skin, with high mortality rates. We report the first case of rhino-orbital co-infection by these pathogens in a diabetic patient, resulting in irreversible vision loss. The patient presented with headache and facial swelling; imaging and endoscopy revealed sinus disease with purulent discharge. Following endoscopic sinus debridement, laboratory diagnosis was confirmed by integrating microscopic staining, fungal culture, and PCR. While early surgical intervention combined with amphotericin B therapy led to clinical improvement, the vision loss persisted. This case underscores the diagnostic challenges of rare fungal co-infections and emphasises the necessity of prompt combined surgical and antifungal intervention to improve outcomes.</div></div>","PeriodicalId":11329,"journal":{"name":"Diagnostic microbiology and infectious disease","volume":"115 3","pages":"Article 117341"},"PeriodicalIF":1.8,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147387749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First case of pulmonary tuberculosis caused by Mycobacterium pinnipedii in Spain: a case report and review of the literature","authors":"Miguel Fernández-Huerta ,&nbsp;Carolina Santamaría-Valencia ,&nbsp;María-Isolina Campos-Herrero ,&nbsp;Guillermo Pérez-Mendoza ,&nbsp;Laura Herrera-León ,&nbsp;Ana Bordes-Benítez ,&nbsp;José-Antonio Caminero","doi":"10.1016/j.diagmicrobio.2026.117350","DOIUrl":"10.1016/j.diagmicrobio.2026.117350","url":null,"abstract":"<div><div>Usually associated with marine mammals, <em>Mycobacterium pinnipedii</em> infection in humans may occur, primarily among animal keepers. We describe a human tuberculosis case caused by <em>M. pinnipedii</em> in a veterinary scientist in Spain, secondary to a contact with an infected sea-lion. Surveillance of zoonotic tuberculosis is critical for informing global control strategies.</div></div>","PeriodicalId":11329,"journal":{"name":"Diagnostic microbiology and infectious disease","volume":"115 3","pages":"Article 117350"},"PeriodicalIF":1.8,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147387751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}